The invention relates to a dynamic MOS circuit comprised of a series connection of a first control MOS-FET, a discharge MOS-FET whose drain input is connected to a bootstrap capacitor, and a first switching MOS-FET. The circuit further comprises a second series connection of a second control MOS-FET and a second switching transistor activatable via the discharge MOS-FET.
An important feature of a MOS circuit, as is known, is its dynamic behavior. Related to this is the dependency of the switching speed upon the load capacitances, since with an increasing load, the switching speed decreases. In addition, the height of the output level is to be noted which should lie as close as possible to the operating voltage. From Electronics, June 30, 1981, Page 128, incorporated herein by reference, a dynamic MOS-circuit is known which switches or connects high load capacitances and exhibits an output voltage which corresponds approximately to the operating voltage. This driver module consists of an input inverter and two switching stages with a bootstrap capacitor decoupled from the input of the output transistor. In the case of a low-value input signal, the capacitor is charged so that a transistor, activated by the input signal, reduces a flowing-off of the charge. The voltage at the capacitor here lies below the operating voltage. If the input signal increases, the output transistor is activated, in dependence on the capacitor voltage, via the above-mentioned discharge transistor. It is disadvantageous here that the control voltage generated in this fashion has a relatively low maximum value. Moreover, the edge steepness of the output signal is dependent upon the edge steepness of the input signal. A shallow rise is automatically transmitted from the input to the output. However, signal edges which are as steep as possible are desired.